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Re: Valley Rafters

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As I said, "It's maigic".

Thor Tandy P.Eng MIStructE
Victoria, BC
vicpeng(--nospam--at)telus.net
----- Original Message -----
Sent: Tuesday, September 13, 2005 11:18 AM
Subject: RE: Valley Rafters

If I were you guys and found these conditions in Alaska ? I would not recommend replacing as is.  What you guys need is nice volcanic eruption on Mount Shasta or something and 3 or 4 inches of ash to help speed up gravity.

 

I have seen old building roofs that appear to be defying gravity. I have also seen a few roofs and floors partially collapse or be in the process there of.   I think there is some law in physics that everything in the end will come to it?s most stable state.

 


From: S. Gordin [mailto:mailbox(--nospam--at)sgeconsulting.com]
Sent: Tuesday, September 13, 2005 10:03 AM
To: seaint(--nospam--at)seaint.org
Subject: Re: Valley Rafters

 

When I first saw something like this, I had to call Dennis Wish to ask him if this was for real.  It was.  All roofs all over a huge apartment complex, may be, 20 years old.  Some of the 2x4 rafters had cracked, most sagged under the weight of the concrete tile roof.

 

I came up with the repair details and specs, they paid me OK.  However, they indicated that they were not going to do anything beyond the replacement of the broken rafters.

 

What could I do? Seriously (as they said), it had been there for 20 years, "nobody got hurt", and (as I know) there is no snow below 2,000 feet in Southern California... 

 

Steve Gordin SE
Irvine CA

    

----- Original Message -----

Sent: Tuesday, September 13, 2005 10:52 AM

Subject: Re: Valley Rafters

 

Another tidbit on Hips. After Northridge Earthquake I investigated several apartments and houses.

To my amazement On stick framed roofs I encountered several long span hips and valleys (+25') where the framer spliced 2x8 or 2x10 at midspan. An engineers dream of course.  The splices were about 2-3 ft. long with a taper cut from top to bottom of member. 3-4 nails holding it together. These were clean cuts that went like a puzzle, some I had to look 3 times to make sure of what I was seeing.

As Nels stated earlier how do you justify this ??  Some had been there for over 40 years.

Yes, there was deflection but most people are unaware or cannot even see it.

 

 

Joe Venuti
Johnson & Nielsen Associates
Palm Springs, CA